Thứ Bảy, 23 tháng 2, 2008

1. Dot matrix printers: These are the most common and the cheapest type of computer printers. They are aptly named dot matrix printers because they can only print in the form of dots.2. Ink jet Printers: These printers are also known as bubble jet printers. Their mode of operation is such that they spray tiny ink jets on to the paper in a dot matrix pattern. In a way, they are similar to dot matrix printers except that here, the print head consists of ink nozzles rather than pins. The quality is, however, far superior than the traditional dot matrix printers because the head consists of many nozzles and the 'dots' overlap as the ink is sprayed. The ink is stored in a disposable ink cartridge.3. Laser printer: This is a high-speed printer that uses laser technology to print. The laser recreates the image on a negatively charged drum, which attracts the positively charged ink to the area of an image. The negatively charged paper attracts the positively charged ink.4. Thermal Printer: A printer that uses heated pins to print images onto heat-sensitive paper. The pins are electrically heated and brought into contact with the specially treated paper. The coating on the paper discolors when heated in this way.5. Plotters: A plotter is a vector based output device that is used for constructing high quality drawings. It holds pens on paper and can draw curved lines. The text is drawn in the form of images.6. Plotters can draw in black and white or in color. Color plotters have a set of color pens. A plotter selects a pen from the predefined position. A plotter can be connected to the port, which is normally used by a printer.